DRM: i915: add mode setting support

This commit adds i915 driver support for the DRM mode setting APIs.
Currently, VGA, LVDS, SDVO DVI & VGA, TV and DVO LVDS outputs are
supported.  HDMI, DisplayPort and additional SDVO output support will
follow.

Support for the mode setting code is controlled by the new 'modeset'
module option.  A new config option, CONFIG_DRM_I915_KMS controls the
default behavior, and whether a PCI ID list is built into the module for
use by user level module utilities.

Note that if mode setting is enabled, user level drivers that access
display registers directly or that don't use the kernel graphics memory
manager will likely corrupt kernel graphics memory, disrupt output
configuration (possibly leading to hangs and/or blank displays), and
prevent panic/oops messages from appearing.  So use caution when
enabling this code; be sure your user level code supports the new
interfaces.

A new SysRq key, 'g', provides emergency support for switching back to
the kernel's framebuffer console; which is useful for testing.

Co-authors: Dave Airlie <airlied@linux.ie>, Hong Liu <hong.liu@intel.com>

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 302 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/dvo_sil164.c b/drivers/gpu/drm/i915/dvo_sil164.c
new file mode 100644
index 000000000000..033a4bb070b2
--- /dev/null
+++ b/drivers/gpu/drm/i915/dvo_sil164.c
@@ -0,0 +1,302 @@
+/**************************************************************************
+
+Copyright © 2006 Dave Airlie
+
+All Rights Reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sub license, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice (including the
+next paragraph) shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+**************************************************************************/
+
+#include "dvo.h"
+
+#define SIL164_VID 0x0001
+#define SIL164_DID 0x0006
+
+#define SIL164_VID_LO 0x00
+#define SIL164_VID_HI 0x01
+#define SIL164_DID_LO 0x02
+#define SIL164_DID_HI 0x03
+#define SIL164_REV    0x04
+#define SIL164_RSVD   0x05
+#define SIL164_FREQ_LO 0x06
+#define SIL164_FREQ_HI 0x07
+
+#define SIL164_REG8 0x08
+#define SIL164_8_VEN (1<<5)
+#define SIL164_8_HEN (1<<4)
+#define SIL164_8_DSEL (1<<3)
+#define SIL164_8_BSEL (1<<2)
+#define SIL164_8_EDGE (1<<1)
+#define SIL164_8_PD   (1<<0)
+
+#define SIL164_REG9 0x09
+#define SIL164_9_VLOW (1<<7)
+#define SIL164_9_MSEL_MASK (0x7<<4)
+#define SIL164_9_TSEL (1<<3)
+#define SIL164_9_RSEN (1<<2)
+#define SIL164_9_HTPLG (1<<1)
+#define SIL164_9_MDI (1<<0)
+
+#define SIL164_REGC 0x0c
+
+struct sil164_save_rec {
+	uint8_t reg8;
+	uint8_t reg9;
+	uint8_t regc;
+};
+
+struct sil164_priv {
+	//I2CDevRec d;
+	bool quiet;
+	struct sil164_save_rec save_regs;
+	struct sil164_save_rec mode_regs;
+};
+
+#define SILPTR(d) ((SIL164Ptr)(d->DriverPrivate.ptr))
+
+static bool sil164_readb(struct intel_dvo_device *dvo, int addr, uint8_t *ch)
+{
+	struct sil164_priv *sil = dvo->dev_priv;
+	struct intel_i2c_chan *i2cbus = dvo->i2c_bus;
+	u8 out_buf[2];
+	u8 in_buf[2];
+
+	struct i2c_msg msgs[] = {
+		{
+			.addr = i2cbus->slave_addr,
+			.flags = 0,
+			.len = 1,
+			.buf = out_buf,
+		},
+		{
+			.addr = i2cbus->slave_addr,
+			.flags = I2C_M_RD,
+			.len = 1,
+			.buf = in_buf,
+		}
+	};
+
+	out_buf[0] = addr;
+	out_buf[1] = 0;
+
+	if (i2c_transfer(&i2cbus->adapter, msgs, 2) == 2) {
+		*ch = in_buf[0];
+		return true;
+	};
+
+	if (!sil->quiet) {
+		DRM_DEBUG("Unable to read register 0x%02x from %s:%02x.\n",
+			  addr, i2cbus->adapter.name, i2cbus->slave_addr);
+	}
+	return false;
+}
+
+static bool sil164_writeb(struct intel_dvo_device *dvo, int addr, uint8_t ch)
+{
+	struct sil164_priv *sil= dvo->dev_priv;
+	struct intel_i2c_chan *i2cbus = dvo->i2c_bus;
+	uint8_t out_buf[2];
+	struct i2c_msg msg = {
+		.addr = i2cbus->slave_addr,
+		.flags = 0,
+		.len = 2,
+		.buf = out_buf,
+	};
+
+	out_buf[0] = addr;
+	out_buf[1] = ch;
+
+	if (i2c_transfer(&i2cbus->adapter, &msg, 1) == 1)
+		return true;
+
+	if (!sil->quiet) {
+		DRM_DEBUG("Unable to write register 0x%02x to %s:%d.\n",
+			  addr, i2cbus->adapter.name, i2cbus->slave_addr);
+	}
+
+	return false;
+}
+
+/* Silicon Image 164 driver for chip on i2c bus */
+static bool sil164_init(struct intel_dvo_device *dvo,
+			struct intel_i2c_chan *i2cbus)
+{
+	/* this will detect the SIL164 chip on the specified i2c bus */
+	struct sil164_priv *sil;
+	unsigned char ch;
+
+	sil = kzalloc(sizeof(struct sil164_priv), GFP_KERNEL);
+	if (sil == NULL)
+		return false;
+
+	dvo->i2c_bus = i2cbus;
+	dvo->i2c_bus->slave_addr = dvo->slave_addr;
+	dvo->dev_priv = sil;
+	sil->quiet = true;
+
+	if (!sil164_readb(dvo, SIL164_VID_LO, &ch))
+		goto out;
+
+	if (ch != (SIL164_VID & 0xff)) {
+		DRM_DEBUG("sil164 not detected got %d: from %s Slave %d.\n",
+			  ch, i2cbus->adapter.name, i2cbus->slave_addr);
+		goto out;
+	}
+
+	if (!sil164_readb(dvo, SIL164_DID_LO, &ch))
+		goto out;
+
+	if (ch != (SIL164_DID & 0xff)) {
+		DRM_DEBUG("sil164 not detected got %d: from %s Slave %d.\n",
+			  ch, i2cbus->adapter.name, i2cbus->slave_addr);
+		goto out;
+	}
+	sil->quiet = false;
+
+	DRM_DEBUG("init sil164 dvo controller successfully!\n");
+	return true;
+
+out:
+	kfree(sil);
+	return false;
+}
+
+static enum drm_connector_status sil164_detect(struct intel_dvo_device *dvo)
+{
+	uint8_t reg9;
+
+	sil164_readb(dvo, SIL164_REG9, &reg9);
+
+	if (reg9 & SIL164_9_HTPLG)
+		return connector_status_connected;
+	else
+		return connector_status_disconnected;
+}
+
+static enum drm_mode_status sil164_mode_valid(struct intel_dvo_device *dvo,
+					      struct drm_display_mode *mode)
+{
+	return MODE_OK;
+}
+
+static void sil164_mode_set(struct intel_dvo_device *dvo,
+			    struct drm_display_mode *mode,
+			    struct drm_display_mode *adjusted_mode)
+{
+	/* As long as the basics are set up, since we don't have clock
+	 * dependencies in the mode setup, we can just leave the
+	 * registers alone and everything will work fine.
+	 */
+	/* recommended programming sequence from doc */
+	/*sil164_writeb(sil, 0x08, 0x30);
+	  sil164_writeb(sil, 0x09, 0x00);
+	  sil164_writeb(sil, 0x0a, 0x90);
+	  sil164_writeb(sil, 0x0c, 0x89);
+	  sil164_writeb(sil, 0x08, 0x31);*/
+	/* don't do much */
+	return;
+}
+
+/* set the SIL164 power state */
+static void sil164_dpms(struct intel_dvo_device *dvo, int mode)
+{
+	int ret;
+	unsigned char ch;
+
+	ret = sil164_readb(dvo, SIL164_REG8, &ch);
+	if (ret == false)
+		return;
+
+	if (mode == DRM_MODE_DPMS_ON)
+		ch |= SIL164_8_PD;
+	else
+		ch &= ~SIL164_8_PD;
+
+	sil164_writeb(dvo, SIL164_REG8, ch);
+	return;
+}
+
+static void sil164_dump_regs(struct intel_dvo_device *dvo)
+{
+	uint8_t val;
+
+	sil164_readb(dvo, SIL164_FREQ_LO, &val);
+	DRM_DEBUG("SIL164_FREQ_LO: 0x%02x\n", val);
+	sil164_readb(dvo, SIL164_FREQ_HI, &val);
+	DRM_DEBUG("SIL164_FREQ_HI: 0x%02x\n", val);
+	sil164_readb(dvo, SIL164_REG8, &val);
+	DRM_DEBUG("SIL164_REG8: 0x%02x\n", val);
+	sil164_readb(dvo, SIL164_REG9, &val);
+	DRM_DEBUG("SIL164_REG9: 0x%02x\n", val);
+	sil164_readb(dvo, SIL164_REGC, &val);
+	DRM_DEBUG("SIL164_REGC: 0x%02x\n", val);
+}
+
+static void sil164_save(struct intel_dvo_device *dvo)
+{
+	struct sil164_priv *sil= dvo->dev_priv;
+
+	if (!sil164_readb(dvo, SIL164_REG8, &sil->save_regs.reg8))
+		return;
+
+	if (!sil164_readb(dvo, SIL164_REG9, &sil->save_regs.reg9))
+		return;
+
+	if (!sil164_readb(dvo, SIL164_REGC, &sil->save_regs.regc))
+		return;
+
+	return;
+}
+
+static void sil164_restore(struct intel_dvo_device *dvo)
+{
+	struct sil164_priv *sil = dvo->dev_priv;
+
+	/* Restore it powered down initially */
+	sil164_writeb(dvo, SIL164_REG8, sil->save_regs.reg8 & ~0x1);
+
+	sil164_writeb(dvo, SIL164_REG9, sil->save_regs.reg9);
+	sil164_writeb(dvo, SIL164_REGC, sil->save_regs.regc);
+	sil164_writeb(dvo, SIL164_REG8, sil->save_regs.reg8);
+}
+
+static void sil164_destroy(struct intel_dvo_device *dvo)
+{
+	struct sil164_priv *sil = dvo->dev_priv;
+
+	if (sil) {
+		kfree(sil);
+		dvo->dev_priv = NULL;
+	}
+}
+
+struct intel_dvo_dev_ops sil164_ops = {
+	.init = sil164_init,
+	.detect = sil164_detect,
+	.mode_valid = sil164_mode_valid,
+	.mode_set = sil164_mode_set,
+	.dpms = sil164_dpms,
+	.dump_regs = sil164_dump_regs,
+	.save = sil164_save,
+	.restore = sil164_restore,
+	.destroy = sil164_destroy,
+};